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The Golden Ratio as a Continued Fraction

Reference > Mathematics > The Golden Ratio
 
Please Note: If you arrived here from a site discussing VBM (Vortex Based Math), you can get more information here: Vortex Based Math.

This page (and the next one) could easily fit in theSlick Math! section of the site, because they have math problems which, at a glance, look fairly intimidating, but are actually quite simple and elegant to solve. They are here instead, because they involve The Golden Ratio.

Take a look at the following continuing fraction (the fraction continues on infinitely in the denominator).
 



How in the world shall we solve such a bizarre looking mess? Well, it's not as hard as it might look at first glance. Let's start by setting that expression equal to R.

Notice, now that the part of the expression which is circled in red is identical to the entire expression:
 



From this we conclude that: R = 1 + 1/R. This can be manipulated to create a quadratic equation:

R2 - R - 1 = 0.

That quadratic might not look familiar to you, but you should get used to it, because you'll see it again and again when you're dealing with The Golden Ratio. In fact, do you remember seeing this equation on the first page?

 

If you set b equal to one, you get exactly the same quadratic as the one I just showed you, and you see that the value of the continued fraction is φ, or The Golden Ratio!

On the next page, we'll take a look at a continued radical expression which evaluates in the same way.

Questions

1.
In the continued fraction shown, what would the value be if you replaced all the ones with twos?
2.
What would the value be if you replaced all the leading ones (ones with a plus sign after them) with twos?
3.
What if you replaced all the other ones with twos instead?
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The Golden Ratio in TrigonometryThe Golden Ratio in Trigonometry
The Golden Ratio as a Continued RadicalThe Golden Ratio as a Continued Radical
 

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